Approximately 80% of people infected with Zika do not show any symptoms. Time from exposure to symptoms is likely a few days and symptoms usually last 2-7 days1. Symptoms are usually mild and include:
- Joint pain
- Conjunctivitis (red eyes)
Other symptoms include:
Zika can also be transmitted sexually, even if the infected person has no symptoms at the time; Zika can remain in semen longer than other bodily fluids5. Zika can also be transmitted through blood transfusion and in laboratory and healthcare settings.
A pregnant woman can pass Zika to her fetus during pregnancy5. Zika can lead to devastating consequences, including microcephaly, a serious brain defect that results in a baby’s head being smaller than normal, and can include problems such as eye defects, hearing loss and impaired growth. Zika also may lead to other brain and autoimmune problems, including Guillain-Barré syndrome (GBS), a disorder in which the immune system attacks nerves, leading to weakness and temporary paralysis. Zika virus infection in pregnancy appears to be the cause of a recognizable pattern of congenital anomalies that is consistent and unique6; Congenital Zika infection is being defined and described as cases occur7.
Long-term complications of Zika are unknown, testing for Zika is complicated and there is no vaccine or treatment so vector control is key to preventing vector-borne disease transmission.